1. Field
This invention is in the field of jet-propelled aircraft, such as civil transport planes.
More specifically, the invention concerns an aircraft with at least two jet engines mounted on the aft part of the fuselage.
2. Brief Description of Related Developments
Modern transport planes, particularly civil passenger transport planes, use various configurations for the installation of propulsion systems.
Jet engines, particularly dual-flow jet engines, are the type of engine most used today because of their performance in terms of thrust and specific consumption and their ability to cruise at high speeds, particularly around Mach 0.8, which are considered to meet current civil transport requirements.
On current modern airplanes, the jet engines are most often either mounted under the wing or on the aft part of the fuselage, a configuration called aft-mounted engines, as illustrated in FIG. 1.
In the known way, in an aft-mounted engine configuration, two engines 3 are mounted symmetrically on either side of the vertical plane of symmetry of the aircraft, laterally on the fuselage 2 by means of support structures, engine struts 39.
Such a configuration, an illustration of which is given in U.S. Pat. No. 2,863,620, is used in twin-engine planes, such as the Caravelle SE210 from Sud Aviation or, in a more recent embodiment, such as the CRJ900 from Bombadier.
Some airplanes propelled by more than two jet engines, also have, in addition to jet engines mounted laterally on the fuselage, a third jet engine fitted above or in the fuselage, approximately in the plane of symmetry of the airplane and in the aft part of the fuselage.
In the known configurations of aft-mounted engines on either side of the fuselage, the engines are kept a certain distance from the walls of the fuselage by engine struts, and each engine is provided with a pod in an approximately orbital shape.
These aft engine installation configurations, while functional, have proven relatively heavy and structurally prejudicial, do not appear optimal in terms of aerodynamic drag and are hard to adapt to modern jet engines with high bypass ratios that are heavy, voluminous and require high rigidity for mounting.
Moreover, the development of non-metallic structures for fuselages, particularly structures made of composite materials, makes it more complicated to use the known solutions for aft-mounted jet engines on the fuselage.